irix.c

Netscape NSPR库源码

     * did not timeout
     */
    if (!thread->md.cvar_pollsem_select) {
        rv = _PR_WAIT_SEM(thread->md.cvar_pollsem);
		PR_ASSERT(rv >= 0);
	} else
        rv = 0;
again:
    if(!rv) {
#ifdef _PR_USE_POLL
		pfd.events = POLLIN;
		pfd.fd = thread->md.cvar_pollsemfd;
		rv = _MD_POLL(&pfd, 1, msecs);
#else
		rv = _MD_SELECT(thread->md.cvar_pollsemfd + 1, &rd, NULL,NULL,tvp);
#endif
        if ((rv == -1) && (errno == EINTR)) {
			rv = 0;
			goto again;
		}
		PR_ASSERT(rv >= 0);
	}

    if (rv > 0) {
        /*
         * acquired the semaphore, call uspsema next time
         */
        thread->md.cvar_pollsem_select = 0;
        return PR_SUCCESS;
    } else {
        /*
         * select timed out; must call select, not uspsema, when trying
         * to acquire the semaphore the next time
         */
        thread->md.cvar_pollsem_select = 1;
        return PR_FAILURE;
    }
}

PRStatus _MD_wait(PRThread *thread, PRIntervalTime ticks)
{
    if ( thread->flags & _PR_GLOBAL_SCOPE ) {
	_MD_CHECK_FOR_EXIT();
        if (pr_cvar_wait_sem(thread, ticks) == PR_FAILURE) {
	    _MD_CHECK_FOR_EXIT();
            /*
             * wait timed out
             */
            _PR_THREAD_LOCK(thread);
            if (thread->wait.cvar) {
                /*
                 * The thread will remove itself from the waitQ
                 * of the cvar in _PR_WaitCondVar
                 */
                thread->wait.cvar = NULL;
                thread->state =  _PR_RUNNING;
                _PR_THREAD_UNLOCK(thread);
            }  else {
                _PR_THREAD_UNLOCK(thread);
                /*
             * This thread was woken up by a notifying thread
             * at the same time as a timeout; so, consume the
             * extra post operation on the semaphore
             */
	        _MD_CHECK_FOR_EXIT();
            pr_cvar_wait_sem(thread, PR_INTERVAL_NO_TIMEOUT);
            }
	    _MD_CHECK_FOR_EXIT();
        }
    } else {
        _PR_MD_SWITCH_CONTEXT(thread);
    }
    return PR_SUCCESS;
}

PRStatus _MD_WakeupWaiter(PRThread *thread)
{
    PRThread *me = _PR_MD_CURRENT_THREAD();
    PRIntn is;

	PR_ASSERT(_pr_md_idle_cpus >= 0);
    if (thread == NULL) {
		if (_pr_md_idle_cpus)
        	_MD_Wakeup_CPUs();
    } else if (!_PR_IS_NATIVE_THREAD(thread)) {
		if (_pr_md_idle_cpus)
       		_MD_Wakeup_CPUs();
    } else {
		PR_ASSERT(_PR_IS_NATIVE_THREAD(thread));
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_INTSOFF(is);
		_MD_CVAR_POST_SEM(thread);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
    } 
    return PR_SUCCESS;
}

void create_sproc (void (*entry) (void *, size_t), unsigned inh,
					void *arg, caddr_t sp, size_t len, int *pid)
{
sproc_params sparams;
char data;
int rv;
PRThread *me = _PR_MD_CURRENT_THREAD();

	if (!_PR_IS_NATIVE_THREAD(me) && (_PR_MD_CURRENT_CPU()->id == 0)) {
		*pid = sprocsp(entry,		/* startup func		*/
						inh,        /* attribute flags	*/
						arg,     	/* thread param		*/
						sp,         /* stack address	*/
						len);       /* stack size		*/
	} else {
		sparams.sd.entry = entry;
		sparams.sd.inh = inh;
		sparams.sd.arg = arg;
		sparams.sd.sp = sp;
		sparams.sd.len = len;
		sparams.sd.pid = pid;
		sparams.sd.creator_pid = getpid();
		_PR_LOCK(sproc_list_lock);
		PR_APPEND_LINK(&sparams.links, &sproc_list);
		rv = write(_pr_irix_primoridal_cpu_fd[1], &data, 1);
		PR_ASSERT(rv == 1);
		_PR_UNLOCK(sproc_list_lock);
		blockproc(getpid());
	}
}

/*
 * _PR_MD_WAKEUP_PRIMORDIAL_CPU
 *
 *		wakeup cpu 0
 */

void _PR_MD_WAKEUP_PRIMORDIAL_CPU()
{
char data = '0';
int rv;

	rv = write(_pr_irix_primoridal_cpu_fd[1], &data, 1);
	PR_ASSERT(rv == 1);
}

/*
 * _PR_MD_primordial_cpu
 *
 *		process events that need to executed by the primordial cpu on each
 *		iteration through the idle loop
 */

void _PR_MD_primordial_cpu()
{
PRCList *qp;
sproc_params *sp;
int pid;

	_PR_LOCK(sproc_list_lock);
	while ((qp = sproc_list.next) != &sproc_list) {
		sp = SPROC_PARAMS_PTR(qp);
		PR_REMOVE_LINK(&sp->links);
		pid = sp->sd.creator_pid;
		(*(sp->sd.pid)) = sprocsp(sp->sd.entry,		/* startup func    */
							sp->sd.inh,            	/* attribute flags     */
							sp->sd.arg,     		/* thread param     */
							sp->sd.sp,             	/* stack address    */
							sp->sd.len);         	/* stack size     */
		unblockproc(pid);
	}
	_PR_UNLOCK(sproc_list_lock);
}

PRStatus _MD_CreateThread(PRThread *thread, 
void (*start)(void *), 
PRThreadPriority priority, 
PRThreadScope scope, 
PRThreadState state, 
PRUint32 stackSize)
{
    typedef void (*SprocEntry) (void *, size_t);
    SprocEntry spentry = (SprocEntry)start;
    PRIntn is;
	PRThread *me = _PR_MD_CURRENT_THREAD();	
	PRInt32 pid;
	PRStatus rv;

	if (!_PR_IS_NATIVE_THREAD(me))
		_PR_INTSOFF(is);
    thread->md.cvar_pollsem_select = 0;
    thread->flags |= _PR_GLOBAL_SCOPE;

	thread->md.cvar_pollsemfd = -1;
	if (new_poll_sem(&thread->md,0) == PR_FAILURE) {
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
		return PR_FAILURE;
	}
	thread->md.cvar_pollsemfd =
		_PR_OPEN_POLL_SEM(thread->md.cvar_pollsem);
	if ((thread->md.cvar_pollsemfd < 0)) {
		free_poll_sem(&thread->md);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
		return PR_FAILURE;
	}

    create_sproc(spentry,            /* startup func    */
    			PR_SALL,            /* attribute flags     */
    			(void *)thread,     /* thread param     */
    			NULL,               /* stack address    */
    			stackSize, &pid);         /* stack size     */
    if (pid > 0) {
        _MD_ATOMIC_INCREMENT(&_pr_md_irix_sprocs_created);
        _MD_ATOMIC_INCREMENT(&_pr_md_irix_sprocs);
		rv = PR_SUCCESS;
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        return rv;
    } else {
        close(thread->md.cvar_pollsemfd);
        thread->md.cvar_pollsemfd = -1;
		free_poll_sem(&thread->md);
        thread->md.cvar_pollsem = NULL;
        _MD_ATOMIC_INCREMENT(&_pr_md_irix_sprocs_failed);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        return PR_FAILURE;
    }
}

void _MD_CleanThread(PRThread *thread)
{
    if (thread->flags & _PR_GLOBAL_SCOPE) {
        close(thread->md.cvar_pollsemfd);
        thread->md.cvar_pollsemfd = -1;
		free_poll_sem(&thread->md);
        thread->md.cvar_pollsem = NULL;
    }
}

void _MD_SetPriority(_MDThread *thread, PRThreadPriority newPri)
{
    return;
}

extern void _MD_unix_terminate_waitpid_daemon(void);

void
_MD_CleanupBeforeExit(void)
{
    extern PRInt32    _pr_cpus_exit;

    _MD_unix_terminate_waitpid_daemon();

	_pr_irix_exit_now = 1;
    if (_pr_numCPU > 1) {
        /*
         * Set a global flag, and wakeup all cpus which will notice the flag
         * and exit.
         */
        _pr_cpus_exit = getpid();
        _MD_Wakeup_CPUs();
        while(_pr_numCPU > 1) {
            _PR_WAIT_SEM(_pr_irix_exit_sem);
            _pr_numCPU--;
        }
    }
    /*
     * cause global threads on the recycle list to exit
     */
     _PR_DEADQ_LOCK;
     if (_PR_NUM_DEADNATIVE != 0) {
	PRThread *thread;
    	PRCList *ptr;

        ptr = _PR_DEADNATIVEQ.next;
        while( ptr != &_PR_DEADNATIVEQ ) {
        	thread = _PR_THREAD_PTR(ptr);
		_MD_CVAR_POST_SEM(thread);
                ptr = ptr->next;
        } 
     }
     _PR_DEADQ_UNLOCK;
     while(_PR_NUM_DEADNATIVE > 1) {
	_PR_WAIT_SEM(_pr_irix_exit_sem);
	_PR_DEC_DEADNATIVE;
     }
}

#ifdef _PR_HAVE_SGI_PRDA_PROCMASK
extern void __sgi_prda_procmask(int);
#endif

PRStatus
_MD_InitAttachedThread(PRThread *thread, PRBool wakeup_parent)
{
	PRStatus rv = PR_SUCCESS;

    if (thread->flags & _PR_GLOBAL_SCOPE) {
		if (new_poll_sem(&thread->md,0) == PR_FAILURE) {
			return PR_FAILURE;
		}
		thread->md.cvar_pollsemfd =
			_PR_OPEN_POLL_SEM(thread->md.cvar_pollsem);
		if ((thread->md.cvar_pollsemfd < 0)) {
			free_poll_sem(&thread->md);
			return PR_FAILURE;
		}
		if (_MD_InitThread(thread, PR_FALSE) == PR_FAILURE) {
			close(thread->md.cvar_pollsemfd);
			thread->md.cvar_pollsemfd = -1;
			free_poll_sem(&thread->md);
			thread->md.cvar_pollsem = NULL;
			return PR_FAILURE;
		}
    }
	return rv;
}

PRStatus
_MD_InitThread(PRThread *thread, PRBool wakeup_parent)
{
    struct sigaction sigact;
	PRStatus rv = PR_SUCCESS;

    if (thread->flags & _PR_GLOBAL_SCOPE) {
		thread->md.id = getpid();
        setblockproccnt(thread->md.id, 0);
		_MD_SET_SPROC_PID(getpid());	
#ifdef _PR_HAVE_SGI_PRDA_PROCMASK
		/*
		 * enable user-level processing of sigprocmask(); this is an
		 * undocumented feature available in Irix 6.2, 6.3, 6.4 and 6.5
		 */
		__sgi_prda_procmask(USER_LEVEL);
#endif
		/*
		 * set up SIGUSR1 handler; this is used to save state
		 */
		sigact.sa_handler = save_context_and_block;
		sigact.sa_flags = SA_RESTART;
		/*
		 * Must mask clock interrupts
		 */
		sigact.sa_mask = timer_set;
		sigaction(SIGUSR1, &sigact, 0);


		/*
		 * PR_SETABORTSIG is a new command implemented in a patch to
		 * Irix 6.2, 6.3 and 6.4. This causes a signal to be sent to all
		 * sprocs in the process when one of them terminates abnormally
		 *
		 */
		if (prctl(PR_SETABORTSIG, SIGKILL) < 0) {
			/*
			 *  if (errno == EINVAL)
			 *
			 *	PR_SETABORTSIG not supported under this OS.
			 *	You may want to get a recent kernel rollup patch that
			 *	supports this feature.
			 */
		}
		/*
		 * SIGCLD handler for detecting abormally-terminating
		 * sprocs and for reaping sprocs
		 */
		sigact.sa_handler = sigchld_handler;
		sigact.sa_flags = SA_RESTART;
		sigact.sa_mask = ints_off;
		sigaction(SIGCLD, &sigact, NULL);
    }
	return rv;
}

/*
 * PR_Cleanup should be executed on the primordial sproc; migrate the thread
 * to the primordial cpu
 */

void _PR_MD_PRE_CLEANUP(PRThread *me)
{
PRIntn is;
_PRCPU *cpu = _pr_primordialCPU;

	PR_ASSERT(cpu);

	me->flags |= _PR_BOUND_THREAD;	

	if (me->cpu->id != 0) {
		_PR_INTSOFF(is);
		_PR_RUNQ_LOCK(cpu);
		me->cpu = cpu;
		me->state = _PR_RUNNABLE;
		_PR_ADD_RUNQ(me, cpu, me->priority);
		_PR_RUNQ_UNLOCK(cpu);
		_MD_Wakeup_CPUs();

		_PR_MD_SWITCH_CONTEXT(me);

		_PR_FAST_INTSON(is);
		PR_ASSERT(me->cpu->id == 0);
	}
}

/*
 * process exiting
 */
PR_EXTERN(void ) _MD_exit(PRIntn status)
{
PRThread *me = _PR_MD_CURRENT_THREAD();

	/*
	 * the exit code of the process is the exit code of the primordial
	 * sproc
	 */
	if (!_PR_IS_NATIVE_THREAD(me) && (_PR_MD_CURRENT_CPU()->id == 0)) {
		/*
		 * primordial sproc case: call _exit directly
		 * Cause SIGKILL to be sent to other sprocs
		 */
		prctl(PR_SETEXITSIG, SIGKILL);
		_exit(status);
	} else {
		int rv;
		char data;
		sigset_t set;

		/*
		 * non-primordial sproc case: cause the primordial sproc, cpu 0,
		 * to wakeup and call _exit
		 */
		_pr_irix_process_exit = 1;
		_pr_irix_process_exit_code = status;
		rv = write(_pr_irix_primoridal_cpu_fd[1], &data, 1);
		PR_ASSERT(rv == 1);
		/*
		 * block all signals and wait for SIGKILL to terminate this sproc
		 */
		sigfillset(&set);
		sigsuspend(&set);
		/*
		 * this code doesn't (shouldn't) execute
		 */
		prctl(PR_SETEXITSIG, SIGKILL);
		_exit(status);
	}
}

/*
 * Override the exit() function in libc to cause the process to exit
 * when the primodial/main nspr thread calls exit. Calls to exit by any
 * other thread simply result in a call to the exit function in libc.
 * The exit code of the process is the exit code of the primordial
 * sproc.
 */

void exit(int status)
{
PRThread *me, *thr;
PRCList *qp;

	if (!_pr_initialized)  {
		if (!libc_exit) {

			if (!libc_handle)
				libc_handle = dlopen("libc.so",RTLD_NOW);
			if (libc_handle)
				libc_exit = (void (*)(int)) dlsym(libc_handle, "exit");
		}
		if (libc_exit)
			(*libc_exit)(status);
		else
			_exit(status);
	}

	me = _PR_MD_CURRENT_THREAD();

	if (me == NULL) 		/* detached thread */
		(*libc_exit)(status);

	PR_ASSERT(_PR_IS_NATIVE_THREAD(me) ||
						(_PR_MD_CURRENT_CPU())->id == me->cpu->id);

	if (me->flags & _PR_PRIMORDIAL) {

		me->flags |= _PR_BOUND_THREAD;	

		PR_ASSERT((_PR_MD_CURRENT_CPU())->id == me->cpu->id);
		if (me->cpu->id != 0) {
			_PRCPU *cpu = _pr_primordialCPU;
			PRIntn is;

			_PR_INTSOFF(is);
			_PR_RUNQ_LOCK(cpu);
			me->cpu = cpu;
			me->state = _PR_RUNNABLE;
			_PR_ADD_RUNQ(me, cpu, me->priority);
			_PR_RUNQ_UNLOCK(cpu);
			_MD_Wakeup_CPUs();

			_PR_MD_SWITCH_CONTEXT(me);

			_PR_FAST_INTSON(is);
		}

		PR_ASSERT((_PR_MD_CURRENT_CPU())->id == 0);

		if (prctl(PR_GETNSHARE) > 1) {
#define SPROC_EXIT_WAIT_TIME 5
			int sleep_cnt = SPROC_EXIT_WAIT_TIME;

			/*
			 * sprocs still running; caue cpus and recycled global threads
			 * to exit
			 */
			_pr_irix_exit_now = 1;
			if (_pr_numCPU > 1) {
				_MD_Wakeup_CPUs();
			}
			 _PR_DEADQ_LOCK;
			 if (_PR_NUM_DEADNATIVE != 0) {
				PRThread *thread;
				PRCList *ptr;

				ptr = _PR_DEADNATIVEQ.next;
				while( ptr != &_PR_DEADNATIVEQ ) {
					thread = _PR_THREAD_PTR(ptr);
					_MD_CVAR_POST_SEM(thread);
					ptr = ptr->next;
				} 
			 }

			while (sleep_cnt-- > 0) {
				if (waitpid(0, NULL, WNOHANG) >= 0) 
					sleep(1);
				else
					break;
			}
			prctl(PR_SETEXITSIG, SIGKILL);
		}
		(*libc_exit)(status);
	} else {
		/*
		 * non-primordial thread; simply call exit in libc.
		 */
		(*libc_exit)(status);
	}
}


void
_MD_InitRunningCPU(_PRCPU *cpu)
{
    extern int _pr_md_pipefd[2];

    _MD_unix_init_running_cpu(cpu);
    cpu->md.id = getpid();
	_MD_SET_SPROC_PID(getpid());	
	if (_pr_md_pipefd[0] >= 0) {